Rome private shore excursion for families with kids: skip the line Colosseum tour

The guide for the Colosseum (Rosella) was great. She was informative, pleasant and great with kids. However, the drive between the port and Rome was frightening. Although I specifically requested booster seats for my children when I booked the tour, the driver was unaware of that request and had no child seats. We had no choice but to let the kids use the regular seat belts. On the road to and from Rome, the driver kept closing his eyes as if falling asleep. He would jerk his head up and swerve a bit every time he opened his eye. I spent the entire ride watching him in the rear view mirror, and multiple times, I had to make noise to make sure the driver was awake. When I confronted the driver about his condition, he insisted that he was not falling asleep but that he had a problem with the sun. Either way, he probably should not have been doing the drive. He was better in Rome itself but frightening on the highway.